Conventionally, there is known a vehicle lamp which forms a predetermined light distribution by a columnar light guide arranged along a front cover and a LED light source arranged in the vicinity of the light guide, within a lamp chamber defined by a lamp body and the front cover (for example, Patent Document 1).
Usually, the light guide is arranged so as to slant as it extends laterally or upward from the central side of a vehicle body along the shape of the vehicle body along with a front cover, and includes a reflecting surface having a diffusing step on a rear surface side. Also, the incident light from the LED light source is reflected by the diffusing step, and is emitted in an irradiation direction from a light-emitting surface on the front surface side.
[Patent Document 1] JP-A-2002-367404